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A field survey was conducted in the central Tibetan Plateau (Nam Co) in China for high-time resolution measurements of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM). Average concentrations (± 1 SD) of GEM, PBM, and GOM from November 2014 to March 2015 were 1.11 ± 0.20 ng m−3, 50.8 ± 26.5 pg m−3, and 3.6 ± 3.2 pg m−3, respectively. During the monitoring period, both GEM and GOM exhibited relative stability in their monthly variations, whereas PBM concentrations were significantly higher in winter compared to those in later autumn and early spring. In terms of diurnal variations, the maximum concentration of GEM was typically observed after sunrise, while PBM reached its peak before sunrise, and the highest concentration of GOM was recorded in the afternoon. Vertical convection conditions, photochemical production, and gas-particle partitioning were responsible for the diurnal cycle of atmospheric mercury. Based on modeling results, it was determined that the air mass transported from South Asia significantly impacted atmospheric mercury levels at Nam Co Station. The regions of western and central Nepal, central and eastern Pakistan, and northern India were identified as potential sources of atmospheric mercury at Nam Co. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass, such as plant residues and agricultural waste, holds immense potential as a renewable resource for the production of biofuels, chemicals, and animal feed. However, the efficient degradation of lignocellulose into fermentable sugars remains a significant challenge. Recent research has highlighted the critical role of microbial diversity in lignocellulosic biomass degradation, offering new insights from a biotechnological perspective. The comprehension and utilization of microbial diversity are crucial for developing efficient biotechnological strategies for lignocellulosic biomass degradation. By uncovering the intricate relationships between microbial communities and their enzymatic machinery, researchers can optimize degradation processes, enhance biofuel production, and contribute to a more sustainable bio‐based economy. Microorganisms, including bacteria, fungi, and archaea, possess diverse enzymatic capabilities, allowing them to secrete a plethora of lignocellulolytic enzymes. Microbial organisms inhabiting extreme environments, such as the rumen, hot and cold springs, deep sea trenches, and acidic and alkaline pH environments, exhibit significant potential in generating enzymes, including hemicellulolytic and lignocellulolytic enzymes, which possess superior biochemical properties essential for industrial bioconversion applications. This review explores the ability of lignocellulosic enzymes from microbial sources to efficiently break down the lignocellulosic biomass and their potential applications in industrial biotechnology. [ABSTRACT FROM AUTHOR]

Dust storms occur frequently in northern China and greatly influence the regional ecology/environment, human health, and security, as well as the global climate, and this is especially true regarding the occurrence of mega dust storms. Many archives reveal dramatic strengthening of China’s dust storms (CDS) between 1850 and 1900, but the reason remains poorly understood. By comparing the episode of dramatic strengthening of CDS to the well-established history of anthropogenic activity and climatic change, this study revealed that the episode occurred precisely in the 1850s and was caused mainly by climate change related to atmospheric circulation anomalies, especially a substantially strengthened East Asian winter monsoon (EAWM); anthropogenic factors acted only to exacerbate the effects of the underlying climatic factors. Under a scenario of continuous warming, the occurrence probability of mega dust storms in China is anticipated to diminish due to the future weakening of the EAWM and an increase in precipitation in the potential sources of Asian mineral dust. [ABSTRACT FROM AUTHOR]

Particulate-bound mercury (PBM) has a large dry-deposition rate and removal coefficient, both of which import mercury into terrestrial and marine ecosystems, causing global environmental problems. In order to illustrate the concentration characteristics, main sources, and health risk of PBM in the atmospheric environment during the spring dust storm period in Xi'an in 2022, PM2.5 samples were collected in Xi'an in March 2022. The concentration of PBM and the PM2.5 composition, including water-soluble ions and elements, were analyzed. The input of dust caused a significant increase in the concentration of PBM, Ca2+, Na+, Mg2+, SO42−, and metal elements in the aerosol. The research results revealed that the dust had a strong enrichment influence on the atmospheric PBM in Xi'an. Anthropogenic mercury emissions and long-distance migration in the sand source area promote the rise in PBM concentration and should be included in the mercury inventory. The values of the risk index for a certain metal (Eri) (572.78–1653.33) and the geo-accumulation index (Igeo) (2.47–4.78) are calculated during this study, showing that atmospheric PBM has a strong pollution level with respect to the ecological environment and that Hg mainly comes from anthropogenic mercury emissions. The non-carcinogenic health risk of atmospheric PBM in children (8.48 × 10−2) is greater than that in adults (1.01 × 10−2). The results show that we need to pay more attention to children's health in the process of atmospheric mercury pollution control. This study discusses the distribution characteristics of PBM during spring sandstorms and the effects of atmospheric mercury on residents' health, providing a basis for studying the sustainable development of environmental health and formulating effective strategies for mercury emission control. [ABSTRACT FROM AUTHOR]

Abstract Nowadays, environmental problems have gradually become the focus of world attention. In recent years, heat waves in many parts of Europe have increased ozone concentrations, fuelling ozone pollution. Therefore, this paper investigates the spatial and temporal distribution of tropospheric column ozone concentrations in South-western Europe, future trend changes, influencing factors, and potential source regions based on remotely sensed monitoring data from the OMI (Ozone Monitoring Instrument) from 2011 to 2021. The results show that the areas of high tropospheric column ozone concentrations are mainly concentrated in the northwest, Poland, and southeast coastal areas. At the same time, the monthly variation curve of column ozone concentration is bimodal. Trend change analyses indicate an upward trend in future column ozone concentrations in the southeastern part of the study area. The potential for increases also exists in parts of Germany, France, and Poland, which will need to be monitored. Random forest model projections found a slight decrease in column ozone concentrations in 2022 and 2023 of about 1–4 DU compared to tropospheric column ozone concentrations in 2021. The health risk assessment found that the number of all-cause premature deaths due to exposure to ozone was the highest in Germany. During the summer, when ozone pollution is high, the potential source area in the southeastern part of the study area is located at the border of the three countries, and synergistic management is recommended. In exploring the correlation between the influencing factors and ozone, it was found that there is a significant difference between the long-time and short-time series. In addition, the pathway analysis shows that the population size, distribution density, and forested area in southwestern Europe may be more sensitive to the production of tropospheric ozone.

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aerosol samples (PM2.5) were collected in Xi'an (XN) from 11 August to 11 September 2021 and in Qinling (QL) from 14 July to 24 August 2021, respectively. In addition, ozone (O3) data were collected in order to investigate the characteristics and source areas of PM2.5 and O3 in the Guanzhong Basin (GB). The concentrations of PM2.5, organic carbon (OC), and elemental carbon (EC) in XN (53.40 ± 17.42, 4.61 ± 2.41, and 0.78 ± 0.60 μg m−3, respectively) were higher than those in QL (27.57 ± 8.27, 4.23 ± 1.37, and 0.67 ± 0.53 μg m−3, respectively) in summer. Total water-soluble ions (TWSIIs) accounted for 19.40% and 39.37% of the PM2.5 concentrations in XN and QL, respectively. O3 concentrations in summer were 102.44 ± 35.08 μg m−3 and 47.95 ± 21.63 μg m−3 in XN and QL, respectively, and they showed a significant correlation with Ox. The positive matrix factorization (PMF) model identified three main sources in XN and QL, including coal combustion source (COB), secondary aerosol (SA), and dust sources (DUSs). The potential source contribution function (PSCF) and a concentration weight trajectory (CWT) model with back-trajectory analysis showed that Inner Mongolia, the interior of Shaanxi, and nearby areas to the southwest were the sources and source areas of carbonaceous matter in XN and QL. The results of this study can contribute to the development of prevention and control policies and guidelines for PM2.5 and O3 in the GB. Furthermore, long-term and sustainable measuring and monitoring of PM2.5 and O3 are necessary, which is of great significance for studying climate change and the sustainable development of the environment. [ABSTRACT FROM AUTHOR]

Nowadays, environmental problems have gradually become the focus of world attention. In recent years, heat waves in many parts of Europe have increased ozone concentrations, fuelling ozone pollution. Therefore, this paper investigates the spatial and temporal distribution of tropospheric column ozone concentrations in South-western Europe, future trend changes, influencing factors, and potential source regions based on remotely sensed monitoring data from the OMI (Ozone Monitoring Instrument) from 2011 to 2021. The results show that the areas of high tropospheric column ozone concentrations are mainly concentrated in the northwest, Poland, and southeast coastal areas. At the same time, the monthly variation curve of column ozone concentration is bimodal. Trend change analyses indicate an upward trend in future column ozone concentrations in the southeastern part of the study area. The potential for increases also exists in parts of Germany, France, and Poland, which will need to be monitored. Random forest model projections found a slight decrease in column ozone concentrations in 2022 and 2023 of about 1–4 DU compared to tropospheric column ozone concentrations in 2021. The health risk assessment found that the number of all-cause premature deaths due to exposure to ozone was the highest in Germany. During the summer, when ozone pollution is high, the potential source area in the southeastern part of the study area is located at the border of the three countries, and synergistic management is recommended. In exploring the correlation between the influencing factors and ozone, it was found that there is a significant difference between the long-time and short-time series. In addition, the pathway analysis shows that the population size, distribution density, and forested area in southwestern Europe may be more sensitive to the production of tropospheric ozone. [ABSTRACT FROM AUTHOR]

This article presents the results of temporal and spatial distribution of aerosol particles and microadmixtures included into them (polycyclic aromatic hydrocarbons and polychlorinated biphenyls) in the near-water layer of the atmosphere above Lake Baikal obtained during a ship expedition from July 18 to July 24, 2022. During the study period, in the lake near-water atmosphere, for the most part, low values of mass and number concentration of aerosol particles and resistant organic pollutants (polycyclic aromatic hydrocarbon (PAHs) and polychlorinated biphenyl (PCBs)) were observed when compared to the fire hazard periods of 2016–2020. During the expedition, the PAHs content in the atmosphere varied from 0.071 to 2.6 ng/m3, which is lower than the concentrations established during the fires (0.22–133 ng/m3). Increased concentrations of the studied components were found only in some areas of southern Baikal, where the formation of aerosol structure occurred due to local pollution sources situated in the populated near-shore areas (namely, Listvyanka, Kultuk, Slyudyanka, and Baikalsk) and at the moment of transfer of polluted air masses northwestward to the lake from Irkutsk and Angarsk. In the aerosol samples from background areas, a PAHs group with two or three benzene rings dominated mainly by naphthalene and phenanthrene. Near local sources in the southern part of Lake Baikal, the proportion of PAHs with four, five, and six benzene rings (fluoranthene > pyrene > benz(b)fluoranthene) increased; they are of pyrogenic origin and are formed at high temperature processes of organic fuel combustion (while combusting coal, wood, and liquid fuel). We revealed a positive correlation between the content of aerosol particles and PAHs. The concentrations of aerosol particles (1.0–13.7 µg/m3) and benz(а)pyrene (0.01–0.22 ng/m3) rated in Russia did not exceed the MAC. Despite the prohibition of production and limited use of PCBs, their traces were found in various industrial and background regions worldwide. It is shown that polychlorinated biphenyls content in Lake Baikal near-water atmosphere (0.48–5.63 pg/m3) is comparable to the concentrations observed in background regions worldwide (0.04–25 pg/m3). [ABSTRACT FROM AUTHOR]

Coke production is an important source of environmental polycyclic aromatic compounds (PACs), including parent polycyclic aromatic hydrocarbons (PAHs) and their derivatives. The focus near coking plants has primarily been on parent-PAH contamination, with less attention given to highly toxic derivatives. In this study, soil samples were collected from both within and outside of a coking plant. The concentrations of parent-PAHs and their derivatives, including methylated-PAHs, oxygenated-PAHs, and nitrated-PAHs, were examined. Spatial interpolation was employed to determine their spatial distribution patterns. Methods for identifying potential sources and conducting incremental lifetime cancer risk analysis were used. This could achieve a comprehensive understanding of the status of PAC pollution and the associated health risks caused by coke production. The concentrations of total PACs inside the plant ranged from 7.4 to 115.8 mg/kg, higher than those outside (in the range of 0.2 to 65.7 mg/kg). The spatial distribution of parent-PAH concentration and their derivatives consistently decreased with increasing distance from the plant. A significant positive correlation (p < 0.05) among parent-PAHs and their derivatives was observed, indicating relatively consistent sources. Based on diagnostic ratios, the potential emission sources of soil PACs could be attributed to coal combustion and vehicle emissions, while principal component analysis–multiple linear regression further indicated that primary emissions and secondary formation jointly influenced the PAC content, accounting for 60.4% and 39.6%, respectively. The exposure risk of soil PACs was dominated by 16 priority control PAHs; the non-priority PAHs' contribution to the exposure risk was only 6.4%. [ABSTRACT FROM AUTHOR]

The hourly concentrations of eight air pollutants relevant for human health and climate (PM2.5, PM10, O3, NO, NO2, NOx, SO2, and CO) were investigated for 1 year (January 2018 to December 2018) at an urban location of a megacity in the Middle East (Tehran, Iran). The spatial distributions of air pollutants were detected via inter-site correlations and coefficients of divergence. The most likely predominant atmospheric processes and sources were determined by interpreting the seasonal, weekly, and diel patterns of air pollutants and the lagged correlations among pollutants. The effect of meteorological factors upon the air pollutants was evaluated by investigating the relationships with key weather factors. The locations of the possible local sources were identified by integrating atmospheric circulation and air pollutant data through bivariate polar plots and conditional bivariate probability function. Potential transboundary source areas were detected using potential source contribution function and concentration-weighted trajectory. Results show that emission factors, weather, and photochemical processes mainly shape the diel and weekly cycles of air pollutants. Compared to other pollutants, daily cycles of SO2 are quite different among sites and show both bimodal and unimodal patterns. While the WPSCF map for O3 does not show a remarkable pattern, primary gaseous pollutants presented similar distribution patterns with the most potential source areas with high WPSCF values from the western areas. By providing useful information on air pollutants at local and transboundary scales, the current study finally empowers general considerations upon the atmospheric processes and air quality status over the Tehran metropolitan area. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution poses a significant environmental challenge on a global scale. In the semi‐arid region of western Liaoning, China, agricultural films have been widely utilized to enhance crop production over an extended period. However, there is a scarcity of research on the presence of MPs in the soil of farmlands in this area. Consequently, a total of 25 dryland soil samples from western Liaoning that had been mulched for more than 10 years and had been used to grow a variety of crops were gathered for the current study. The abundance, particle size, shape, and potential sources of MPs were examined, and the impact of different crop varieties on MPs characteristics was investigated. MPs abundance ranged from 6960 ± 1939 to 34,710 ± 9974 n kg−1, with the average and median of 14,305 ± 7015 and 12,270 ± 1621 n kg−1. MPs with sizes of less than 0.05, 0.05–0.1, and 0.1–0.4 mm were found in 42.7%, 33.8%, and 18.8% of cases, respectively. The most common shapes were fragments, microbeads, and films, with percentages of 47.1%, 22.3%, and 17.9%, respectively. A total of three polymers were found: polyethylene, polypropylene, and polystyrene in a proportion of 44.8%, 43.7%, and 11.5%, respectively. Based on the shape of the MPs, principal component analysis and cluster analysis revealed that the primary sources for MPs may be agricultural mulch, irrigation water, and the weathering of hard plastics like agricultural packaging. Compared to other crop types, soils growing sweet potato and peanut had significantly higher MP abundances. Moreover, soils growing sweet potato had significantly higher percentages of MPs with 0.05–0.1 mm particle size. Regardless of the crop type grown, fragments are the most common shape, while the proportion of other shapes varies depending on the crop type. The aforementioned findings suggest that MP pollution in farmland soil in western Liaoning is more severe and that the kind of crop cultivation affects the characteristics of MPs in the soil. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By combining atmospheric environment observational data, we expounded the characteristics, types, and potential source regions of air pollution in Zhengzhou using the characteristic radar chart, potential source contribution factor analysis, and concentration weighted trajectory analysis. We also calculated the excess risk (ER) of death caused by excessive air pollutants and explored a typical pollution process. The results showed that the average PM2.5 concentration in autumn (October and November 2020) (55.5 μg/m3) was lower than that in winter (December 2020 and January 2021) (83.5 μg/m3), and January was the month most seriously affected by dust pollution. Secondary pollution was mainly concentrated in December and January, while dust pollution was mainly concentrated in October and January. Dust pollution was mainly affected by long-distance transport in the northwest, and the remaining pollution (except comprehensive pollution) was mainly affected by short-distance transport in the eastern cities (Jining and Xuzhou). The ER values were mainly attributed to excessive PM10, PM2.5, and NO2. Secondary pollution and dust pollution were the main contributors to ER. During the typical pollution process, in the dust period (stage I), air masses were mainly affected by long-distance transport in the northwest, which displayed higher wind speed and lower relative humidity. Moreover, the PM2.5/PM10 value was below 0.4. During the heavy PM2.5 pollution period (stage III), air masses were mainly affected by local transport in the northeast, which displayed lower wind speed and higher relative humidity. This period showed clear secondary pollution and more severe motor vehicle emissions. [ABSTRACT FROM AUTHOR]

• The concentration of phthalates in the Yellow River is higher. • DMP, DEP, and DiBP were the most frequently encountered components. • Control of construction land release and lake pollution sources is critical. • DNOP and DiBP demonstrate low to moderate risk concentrations. Phthalate esters (PAEs), recognized as endocrine disruptors, are released into the environment during usage, thereby exerting adverse ecological effects. This study investigates the occurrence, sources, and risk assessment of PAEs in surface water obtained from 36 sampling points within the Yellow River and Yangtze River basins. The total concentration of PAEs in the Yellow River spans from 124.5 to 836.5 ng/L, with Dimethyl phthalate (DMP) (75.4 ± 102.7 ng/L) and Diisobutyl phthalate (DiBP) (263.4 ± 103.1 ng/L) emerging as the predominant types. Concentrations exhibit a pattern of upstream (512.9 ± 202.1 ng/L) > midstream (344.5 ± 135.3 ng/L) > downstream (177.8 ± 46.7 ng/L). In the Yangtze River, the total concentration ranges from 81.9 to 441.6 ng/L, with DMP (46.1 ± 23.4 ng/L), Diethyl phthalate (DEP) (93.3 ± 45.2 ng/L), and DiBP (174.2 ± 67.6 ng/L) as the primary components. Concentration levels follow a midstream (324.8 ± 107.3 ng/L) > upstream (200.8 ± 51.8 ng/L) > downstream (165.8 ± 71.6 ng/L) pattern. Attention should be directed towards the moderate ecological risks of DiBP in the upstream of HH, and both the upstream and midstream of CJ need consideration for the moderate ecological risks associated with Di-n-octyl phthalate (DNOP). Conversely, in other regions, the associated risk with PAEs is either low or negligible. The main source of PAEs in Yellow River is attributed to the release of construction land, while in the Yangtze River Basin, it stems from the accumulation of pollutants in lakes and forests discharged into the river. These findings are instrumental for pinpointing sources of PAEs pollution and formulating control strategies in the Yellow and Yangtze Rivers, providing valuable insights for global PAEs research in other major rivers. [Display omitted] [ABSTRACT FROM AUTHOR]

Coke production is an important source of environmental polycyclic aromatic compounds (PACs), including parent polycyclic aromatic hydrocarbons (PAHs) and their derivatives. The focus near coking plants has primarily been on parent-PAH contamination, with less attention given to highly toxic derivatives. In this study, soil samples were collected from both within and outside of a coking plant. The concentrations of parent-PAHs and their derivatives, including methylated-PAHs, oxygenated-PAHs, and nitrated-PAHs, were examined. Spatial interpolation was employed to determine their spatial distribution patterns. Methods for identifying potential sources and conducting incremental lifetime cancer risk analysis were used. This could achieve a comprehensive understanding of the status of PAC pollution and the associated health risks caused by coke production. The concentrations of total PACs inside the plant ranged from 7.4 to 115.8 mg/kg, higher than those outside (in the range of 0.2 to 65.7 mg/kg). The spatial distribution of parent-PAH concentration and their derivatives consistently decreased with increasing distance from the plant. A significant positive correlation (p < 0.05) among parent-PAHs and their derivatives was observed, indicating relatively consistent sources. Based on diagnostic ratios, the potential emission sources of soil PACs could be attributed to coal combustion and vehicle emissions, while principal component analysis–multiple linear regression further indicated that primary emissions and secondary formation jointly influenced the PAC content, accounting for 60.4% and 39.6%, respectively. The exposure risk of soil PACs was dominated by 16 priority control PAHs; the non-priority PAHs’ contribution to the exposure risk was only 6.4%.

Rare earth elements (REEs) and Nd isotopes are frequently employed to determine provenance, although their characteristics and provenances in the surface sediments of mangrove wetlands are rarely analyzed. In this study, a thorough analysis of the characteristics and provenances of REEs and Nd isotopes in the surface sediments of mangrove wetland in the Jiulong River Estuary was carried out. According to the results, the mean concentration of REEs in the surface sediments was 290.9 mg·kg−1, which was greater than the background value. Unpolluted to moderately polluted for La and Ce, as well as a moderate ecological risk for Lu, were indicated by the geoaccumulation index (Igeo) and potential ecological risk of individual factors ( E r i ), respectively. The surface sediments showed substantial negative Eu anomalies but no significant Ce anomalies. The enrichments in LREE and flat HREE patterns are visible in the chondrite-normalized REE patterns. REEs in the surface sediments might be attributed to both natural sources (granite and magmatic rocks) and anthropogenic activities, including coal combustion, vehicle exhaust, steel smelting, and fertilizer, based on the (La/Yb)N-∑REE and ternary (La/Yb)N-(La/Sm)N-(Gd/Yb)N plots. The three-dimensional ∑LREE/∑HREE-Eu/Eu*-εNd(0) plot, when combined with the Nd isotope, further demonstrated that the REEs in the surface sediments appeared to have come from additional nonlocal potential sources. [ABSTRACT FROM AUTHOR]

Per and polyfluoroalkyl substances (PFASs) have attracted major global concerns because some of them are environmentally persistent, bioaccumulative, and toxic. Perfluoroalkyl acids (PFAAs) have been well-characterized in water, soil, and sediment; however, fluorotelomer alcohols and perfluoroalkane sulfonamido substances have been overlooked. In this study, concentrations of three fluorotelomer alcohols and four perfluoroalkane sulfonamido substances were determined in the air at nine locations representing urban, rural-urban transect, and urban areas in the Pearl River Delta region, China to investigate their seasonal and spatial distributions and potential sources. At least two of the targeted PFASs were detected in all air samples in the Pearl River Delta region, with concentrations ranging from 371 pg/sampler to 18700 pg/sampler. Fluorotelomer alcohols were dominant compounds (contributing 46% to the ∑7PFAS concentration on average) in the atmosphere in the Pearl River Delta region. The total concentrations of the seven targeted PFASs were significantly higher in summer than in other seasons in urban areas. PFAS concentrations were positively related to the population density in the Pearl River Delta region. Local diffusive emission and long range transport could be sources of the seven PFASs in the air in the Pearl River Delta region. [ABSTRACT FROM AUTHOR]

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The overuse of antibiotics and the pollution of the ecological environment caused by their emissions had attracted widespread attention. There was little information on the detection and distribution characteristics of antibiotics in coastal environments with complex water-suspended particles interactions and significant salinity changes. In this study, the occurrence, source, and ecological risk of 26 antibiotics, as well as their response mechanisms to anthropogenic activities were studied. Water samples along a typical silty mud coastal area were collected. The total concentration of antibiotics in the coastal water ranged from 8.5 to 132 ng/L. Spatially, the total concentration showed a downward trend along the canal. The results of offshore samples showed that the highest concentrations occurred near the small estuaries and the northwestern sampling sites. This indicated that the small canals provided a large source of pollutants and the antibiotic distribution were also dominated by local hydrodynamic conditions. Based on the results of principal component analysis-multiple linear regression, the domestic sewage and livestock and poultry farming were identified as the predominant sources of antibiotics. The results of the ecological risk assessment showed that 56.8 % sampling sites were in low-risk. The effect of intensity of anthropogenic disturbance on the distribution of antibiotics was represented by the distance between the sampling site and the city center, and the distance value showed a significant negative correlation with the total concentration of antibiotics. However, different kinds of antibiotics showed different patterns: concentrations of tetracyclines and fluoroquinolones had no significant relationship with distance values; sulfonamides, lincosamides, and macrolides decreased with the intensity of anthropogenic disturbance. This study presented a method to quantify the effect of anthropogenic activities, thus provided a new insight of adjust measures to local conditions for the pollution prevention and ecological risk assessment of antibiotics in coastal areas.

Amino acids are an important constituent in organic nitrogen deposition, and changes in the content of their components have a direct impact on the nitrogen input to the ecosystem. From December 2018 to November 2019, 176 precipitation samples were collected at Danjiangkou Reservoir, the source of the middle line of the South–to–North Water Diversion Project, and the variation characteristics of dissolved free amino acids (DFAA) and dissolved combined amino acids (DCAA) were analyzed. The volume-weighted value concentration ranges of DFAA and DCAA were 0.159–1.136 μmol/L and 1.603–7.044 μmol/L, respectively, and amino acids were dominated by DCAA in wet deposition. Our results showed that glutamic acid (Glu), glycine (Gly), and aspartic acid (Asp) were the dominant amino acids in both DFAA and DCAA. The concentration of DFAA was highest in winter, while the concentration of DCAA was in autumn. Dissolved total amino acids (DTAA) were insignificantly correlated with DFAA, whereas they were linearly correlated with DCAA, indicating a significant influence of agricultural activities on DTAA. The analysis of the backward trajectory of air masses showed that amino acids were mainly influenced by proximity inputs around the reservoir. The bioavailability of organic matter was higher in the southeastern of the reservoir than in the northwestern. The wet deposition flux of TDN was 14.096 kg N/ha/year, and the potential ecological impact on water bodies cannot be ignored. This study was conducted to clarify the variation characteristics of amino acids fractions in wet deposition and to provide parameters for regional assessment of amino acids wet deposition. The ecological impact of nitrogen wet deposition on water bodies will be explored to provide a basis for nitrogen pollution control and water quality protection in the middle line of the South–to–North Water Diversion Project. [ABSTRACT FROM AUTHOR]

As new persistent organic compounds, polybrominated diphenyl ethers (PBDEs) have aroused important concern because of their potential bioaccumulation and possible ecological and health risk. To examine the sources and temporal variation of PBDEs in Chaohu Lake in eastern China, the surface sediments from Nanfei River (NFR) and core sediments from four estuaries were measured. It showed that low-brominated congeners were dominant, from MonoBDEs to HeptaBDEs (referred to as Σ39PBDE). Concentrations of ∑39PBDE and the ratios of (BDE-47 + BDE-99 + BDE-100)/(BDE-153 + BDE-154) were much greater in surface sediments than in core sediments. The highest concentration was observed in a site close to the outfall of a municipal sewage treatment plant (MSTP), and the ratio was significantly correlated with ∑39PBDE. These results suggested that PentaBDE and OctaBDE commercial mixtures were widely used around Chaohu Lake and the effluent of municipal sewage was a dominant source of PBDEs to surface sediment. Compared to data from other freshwater systems around the world, the concentrations of BDE-47 and BDE-99 in this study were in the middle of the range of global data, but BDE-183 concentrations were at the high end of the range. Due to restrictions on the usage of PentanBDE and OctaBDE commercial mixtures, reductions of PBDE levels from subsurface to superficial layer were observed in all estuaries. Elevated contribution by MonoBDEs to ∑39PBDE in the estuary of the only outflow river suggests significant congener fractionation. TriBDEs, TetraBDEs, and HexaBDEs appeared to pose low risks in all surface sediments, but moderate to high risks may be expected for PentaBDEs. Overall, the results would contribute to a better understanding of the sources and environmental fate of PBDEs in the studied eutrophicated lake. [ABSTRACT FROM AUTHOR]

The Central Plains Urban Agglomeration (CPUA) is the largest region in central China and suffers from serious air pollution. To reveal the spatiotemporal variations and the sources of fine particulate matter (PM2.5, with an aerodynamic diameter of smaller than 2.5 μm) concentrations of CPUA, multiple and transdisciplinary methods were used to analyse the collected millions of PM2.5 concentration data. The results showed that during 2017 ~ 2020, the yearly mean concentrations of PM2.5 for CPUA were 68.3, 61.5, 58.7, and 51.5 μg/m3, respectively. The empirical orthogonal function (EOF) analysis suggested that high PM2.5 pollution mainly occurred in winter (100.8 μg/m3, 4-year average). The diurnal change in PM2.5 concentrations varied slightly over the season. The centroid of the PM2.5 concentration moved towards the west over time. The spatial autocorrelation analysis indicated that PM2.5 concentrations exhibited a positive spatial autocorrelation in CPUA. The most polluted cities distributed in the northern CPUA (Handan was the centre) formed a high-high agglomeration, and the cities located in the southern CPUA (Xinyang was the centre) formed a low-low agglomeration. The backward trajectory model and potential source contribution function were employed to discuss the regional transportation of PM2.5. The results demonstrated that internal-region and cross-regional transport of anthropogenic emissions were all important to PM2.5 pollution of CPUA. Our study suggests that joint efforts across cities and regions are necessary. [ABSTRACT FROM AUTHOR]

The problems are associated with microplastic (MP) pollution of global concern. However, little is known about the pollution characteristics and sources of MPs in urban green-belt soils. Therefore, this study investigated MP pollution in 11 sampling sites (22 green belts) in Shihezi City. The results showed that the abundance of MPs (0.02–5.00 mm) ranged from 287 ± 100 items/kg dw to 3227 ± 155 items/kg dw (mean + SD). Fibers (69.9%) accounted for the majority of MPs, and the MPs were mainly black (36.7%) and 0.02–0.5 mm (64.8%). The main types of MPs were polystyrene (PS) and polyethylene (PE). Compared with agricultural soil, the color and composition of green-belt soil MPs are diverse, which means that the source of green-belt soil MPs is more diverse. In different types of green-belt soil, MP pollution of industrial green land is more serious. Through cluster analysis and spatial distribution, fragments and fibers were found to have similar sources, mainly originating from food and textile industrial activities. This study provides important information for revealing MP pollutions in urban green-belt soils. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Benzotriazole ultraviolet absorbers (BUVs), as emerging contaminants of extensive use, especially in plastic sports fields, have aroused increasing concern due to their potential human and environmental impacts. However, BUV exposure from plastic sports field dust is still unknown. This study compared BUVs in plastic sports field dust and indoor dust for the first time. The order of the geometric mean concentrations of the total BUVs (ΣBUVs) in plastic sports field dust was indoor badminton courts (11023 ng g -1 ) > basketball courts (4777 ng g -1 ) > plastic tracks (3779 ng g -1 ) > synthetic turf (1920 ng g -1 ) > tennis courts (689 ng g -1 ). The geometric mean concentrations of ΣBUVs in indoor dust (1150 ng g -1 ) were lower than those in most plastic sports field dust. The dominant BUV was 2-hydroxy-4-(octyloxy)benzophenone (UV-531) in plastic sports field dust, while 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-2H-benzotriazole-2-yl)phenol] (UV-360) was the dominant BUV in indoor dust. Releases from plastic track materials, sneaker soles, and friction between them might be important BUV sources in plastic track dust. The average estimated daily intakes of ΣBUVs from plastic sports field dust for general exercisers were lower than those from indoor dust, but those for exercisers with long time or professional athletes might be higher, potentially posing health risks.

Microplastics (MPs) in glaciers of remote areas are a hot topic linking the global transport of atmospheric MPs. The Tibetan Plateau (TP) holds large volume of glaciers, providing an effective way to trace MPs transport. Moreover, MPs in glaciers may have adverse effects on the local ecosystem and human health. In this study, we investigate MPs in snowpits collected from six glaciers across the different domain of the TP. The average abundance of MPs in six snowpits is 339.22 ± 51.85 items L -1 (with size ≥10 μm) measured by Agilent 8700 Laser Direct Infrared Chemical Imaging System (LDIR), represented by relatively high MPs abundance in the southern TP and low in the northern TP. The polymers with lower density, namely polyethylene (PE), polyamide (PA), and rubber, are the main MPs types, which are predominated by fragments with sizes smaller than 100 μm in each snowpit. Sources of MPs on glaciers include local tourism and vehicle traffic emissions of MPs. Meanwhile, long-range atmospheric transport of MPs from surrounded regions cannot be ignored. Backward trajectory analysis indicates cross-boundary transport of atmospheric MPs from South Asia play an important role on MPs deposited onto TP glaciers. Analysis further reveals that MPs in glaciers are associated with atmospheric mineral dust deposition. This study provides new data for the investigation of MPs in glaciers of remote areas, and a reference for studying MPs in the ice cores of TP glaciers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The concentration changes of aerosols have attracted wide-ranging attention during the COVID-19 lockdown (CLD) period, but the studies involving aerosol optical properties (AOPs) are relatively insufficient, mainly AOD (fine-mode AOD (AODf) and coarse-mode AOD (AODc)), aerosol absorption optical depth (AAOD), and aerosol extinction coefficient (AEC). Here, the remote-sensing observations, Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) products, backward-trajectory, and potential-source-contribution models are used to assess the impact of AOPs, vertical distribution, and possible sources on the atmosphere environment in North China Plain (NCP), Central China (CC), Yangtze River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB) during the CLD period. The results demonstrate that both AOD (MODIS) and near-surface AEC (CALIPSO, <2 km) decreased in most areas of China. Compared with previous years (average 2017–2019), the AOD (AEC) of NCP, CC, YRD, PRD, and SB reduced by 3.33% (10.76%), 14.36% (32.48%), 10.80% (29.64%), 31.44% (22.68%), and 15.50% (8.44%), respectively. In addition, MODIS (AODc) and MERRA-2 (AODc) decreased in the five study areas compared with previous years, so the reduction in dust activities also contributed to improving regional air quality during the epidemic. Despite the reduction of anthropogenic emissions (AODf) in most areas of China during the CLD periods, severe haze events (AODf > 0.6) still occurred in some areas. Compared to previous years, there were increases in BC, OC (MERRA-2), and national raw coal consumption during CLD. Therefore, emissions from some key sectors (raw coal heating, thermal power generation, and residential coal) did not decrease, and this may have increased AODf during the CLD. Based on backward -rajectory and potential source contribution models, the study area was mainly influenced by local anthropogenic emissions, but some areas were also influenced by northwestern dust, Southeast Asian biomass burning, and marine aerosol transport. This paper underscores the importance of emissions from the residential sector and thermal power plants for atmospheric pollution in China and suggests that these sources must be taken into account in developing pollution-mitigation plans. [ABSTRACT FROM AUTHOR]

Large-scale open burning of straw residues causes seasonal and severe atmospheric pollution in Northeast China. Previous studies focused on the causes or assessment of atmospheric pollution in a single city. However, studies conducted on the interaction range, degree and policy control of pollutant transport on a large scale are still to be performed. In this study, we propose combined control of straw burning by dividing region the straw burning in Northeast China in recent 20 years, determining the transport routes between main cities, and analyzing the interaction characteristics of straw burning under different scenarios. The fire point data suggest that the most intense straw burning years in Northeast China in the past 20 years occurred in the range from 2014 to 2017, mainly after the autumn harvest (October–November) and before spring cultivation (March–April). The burning areas were concentrated in the belt of Shenyang-Changchun-Harbin, the border of the three provinces and Eastern-Inner Mongolia, and the surrounding area of Hegang and Jiamusi City. The lower number of fire points before 2013 indicates that high-intensity burning has not always been the case, while the sharp decline after 2018 is mainly due to scientific control of straw burning and increased comprehensive utilization of straw. Compared with S2, the PM2.5 concentrations increased by 6.2% in S3 and 18.7% in S4, indicating that burning in three or four provinces at the same time will significantly increase air pollution and exert a regional transmission effect. Straw burning in Northeast China is divided into six main regions based on correlation analysis and satellite fire monitoring. Under typical S3, the case analysis results indicate that there is regional transmission interaction between different cities and provinces, focusing on multi-province border cities, and it is affected by Northwest long airflow, and Southeast and Northeast short airflow. These results provide scientific and technological support for implementing the joint prevention and control plan for straw incineration in Northeast China. [ABSTRACT FROM AUTHOR]

[Introduction]: In Costa Rica, more than 70 % of the public drinking water supply comes from groundwater sources. In the coastal city of Jacó, on the Central Pacific Coast of Costa Rica, tourism activity is essential for economic development and groundwater represents a source for supplying tourists and residents. [Objective]: This research aims to characterize the threats of groundwater contamination to the coastal aquifer of Jacó due to human activities, based on land use analysis, characterization of potential pollution sources and, estimation of the floating population related to tourist activity. [Methodology]: An inventory of potential pollution sources was carried out through the location of human/anthropogenic activities. Potential point, diffuse and linear sources were classified based on the Pollutant Origin Surcharge Hydraulically (POSH) method, as activities with high, medium and low potential generating pollutant load (threat) [Results]: Of the total potential sources, 0.5 % correspond to activities with high potential, 14.0 % medium potential and 23.5 % low potential, and 62.0 % null potential. Out of 129 point pollution sources, 64.3 % were classified as medium threat activities due to the storage and handling of potentially polluting chemicals. Although the sources of high threat are those of lesser occurrence in the study area, they can generate greater negative impacts on groundwater resources. These are located mainly in the urban area of the city where the floating population reaches more than 12 000 people during the holidays, so their potential for pollutant loading could rise during this period. [Conclusions]: The results will be considered in territory planning, which seeks to reduce the probability of groundwater contamination in Jacó.

The Yangtze River Delta (YRD), one of the most economically developed and industrialized regions in China, is confronted with challenges arising from rapid urbanization, particularly environmental pollution. The collection of surface water and sediment samples from forty-nine sites in the YRD was conducted to analyze 2378-substituted polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) congeners. The detected concentrations of PCDD/Fs were 0–5.3 pg TEQ/L in water and 0.12–1493 pg TEQ/g dw in sediment. The PCDD/Fs contamination in the sediment was widespread in the YRD. There were variations in the congener characteristics of PCDD/Fs in surface water and sediment. The proportion of OCDD was significantly lower in surface water samples compared to sediment, while the less chlorine-substituted homologs were found in larger proportions. To understand the partitioning and behavior of dioxins within the water-sediment system, we calculated the organic carbon normalized partition coefficients and fugacity fraction (ff) of PCDD/F congeners. The results revealed that the PCDD/Fs had not attained a state of distributional equilibrium, and the non-specific hydrophobic effect seemed minimally influential on their partitioning between sediment and water. The average ff values, which varied between 0.06 and 0.63, indicated differing migration directions for the PCDD/F congeners. Source identification analysis provided evidence that the dioxins in the river water were primarily attributed to industrial thermal processes. Iron and steel smelting, along with pesticide production and use, were likely responsible for the sediment contamination. This comprehensive analysis underscores the complex nature of PCDD/Fs pollution in the YRD and highlights the necessity for targeted environmental management strategies. • PCDD/Fs contamination in the sediment was widespread in the YRD. • OCDD/F and 1234678-HpCDD/F were the predominant congeners in different media. • PCDFs and high-chlorinated PCDDs exhibited stronger tendency to adsorbed from water to sediment. • PCDD/Fs in water were primarily influenced by industrial thermal processes. • PCDD/Fs in sediment and soil additional affected by production and use of pesticide. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM), including PM2.5 in pig houses, has received increasing attention due to the potential health risks associated with PM. At present, most studies have analyzed PM2.5 in Chinese pig houses utilizing natural ventilation. These results, however, are strongly affected by the internal structure and regional environment, thus limiting their applicability to non-mechanically ventilated pig houses. This experiment was carried out in an environmentally controlled pig house. The animal feeding operation and manure management in the house were typical for Southwest China. To reduce the influence of various environmental factors on PM2.5, the temperature and humidity in the house were maintained in a relatively stable state by using an environmental control system. The concentration of PM2.5 in the pig house was monitored, while the biological contents and chemical composition of PM2.5 were analyzed, and feed, manure, and dust particles were scanned using an electron microscope. Moreover, bacterial and fungal contents and some water-soluble ions in PM2.5 were identified. The results showed that the concentration of PM2.5 in the pig house was strongly affected by pig activity, and a phenomenon of forming secondary particles in the pig house was found, although the transformation intensity was low. The concentration of PM2.5 had negative correlations of 0.27 and 0.18 with ammonia and hydrogen sulfide, respectively. Interestingly, a stronger correlation was observed between ammonia and hydrogen sulfide and ammonia and carbon dioxide concentrations (the concentration of ammonia had stronger positive correlations with hydrogen sulfide and carbon dioxide concentrations at +0.44 and +0.59, respectively). The main potential sources of PM2.5 production were feed and manure. We speculate that manure could contribute to the broken, rough, and angular particles that formed the pig house PM2.5 that easily adhered to other components. [ABSTRACT FROM AUTHOR]

Microfibers, as emerging contaminants, pose a growing threat to the global environment. Microfiber pollution has been one of the hot research topics in environmental science. However, there is no consensus on microfiber definition from ecological and environmental perspectives. The underestimated sources, the distribution in the ocean and the atmosphere, the transport pathway, the potential human exposure, and mitigation strategies of microfibers from a global perspective have not been systemically discussed. So, we aim to discuss and analyze these concerns in this review. Firstly, the definition of microfiber pollutants from the ecological and environmental perspectives is proposed. Secondly, the largest source and some emerging sources of microfibers on the Earth have been explored. Thirdly, the distribution and transmission path of microfibers in the ocean and the atmosphere are discussed. Fourthly, the exposure path of microfibers to the human body is analyzed. Lastly, some applicable measures to control microfiber pollution are proposed from global environmental sustainable development perspectives. [ABSTRACT FROM AUTHOR]

Using conventional meteorological observations, particulate matter observation data, NCEP reanalysis with 1°×1° resolution, GDAS data with 1°×1° resolution, lidar measurements and other data, we have investigated the cause and transport characteristics related to a continuous heavy pollution weather event occurred in Luohe of Henan Province in late November 2018. The main results are as follow. (1) This pollution event is closely related to synoptic situation. In its early stage it was influenced by the stable zonal circulation and surface uniform pressure field, which was beneficial to the accumulation of pollutant. In its middle stage, the weak cold air moved eastward and southward under the control of the upper-level trough and surface transported high, causing the fast increase of pollutants because of detention effect. In its late stage, with the diffusion of low-level easterly cold air and the restore of stable situation, the pollutants continued to accumulate, which led to the continuous heavy pollution. (2) During the heavy pollution caused by PM2.5, the pollution was exacerbated due to the stability and continuance of radiation inversion. During the heavy pollution caused by PM10, the inversion layer disappeared, which was conducive to the transport and deposition of pollutants. During the heavy pollution caused by PM2.5 and PM10, the turbulence near the ground strengthened and formed inversion, resulting in the continuance pollution. (3) There are 5 major transport paths in this event. The pollution from the southwest and easterly paths has a high proportion, whose length is short and height is below 900 hPa. Both the two paths play a significant role in the short distance transport of PM2.5. The pollution from the northwest and northerly paths has a great length, whose initial altitude is between 700 hPa and 600 hPa, showing that the long distance transportation in the upper-level is mainly PM10. (4) Affected by stable conditions and high humidity in the surface layer, the high extinction zones maintain below 600 m, and the shallow boundary layer inhibits vertical diffusion, leading to the accumulation and long time coexisting of fine aerosol particles and dust. (5) This heavy pollution event is the result of the combined influence of local pollution accumulation and upper-level transport. Besides the high contribution of local pollution in Luohe, the high potential source areas are mainly concentrated in the southwest and northeast parts of Henan and the junction of Henan and Shandong, which is an important reason for the development of continuous pollution. During the heavy pollution, the surface northerly winds dominate, while the wind speed of other wind directions is small, which is conducive to the convergence and secondary conversion of pollutants and the pollution aggravating.

One hundred forty-three surface sediment (0–5 cm depth) samples were collected from locations representing industrialized areas, less-industrialized areas, and e-waste recycling areas in the Pearl River Delta (PRD). The spatial distribution of polychlorinated biphenyls (PCBs) and their potential adverse effects on aquatic organisms were investigated. The average PCB concentration in the less-industrialized areas (background) in the PRD was approximately 10 ng/g dry weight (dw), which was generally half that found in the industrialized areas (approximately 22 ng/g dw). Severe PCB contamination, with concentrations ranging from 1000 to 26500 ng/g dw, was found in pond sediments collected from e-waste recycling areas. It is very likely that such contamination would have had adverse effects on the aquatic biota there. PCBs in the e-waste recycling areas were dominated by penta- and hex-PCB congeners, which made them significantly different from those found in other regions, where tri- and tetra-PCB congeners were predominant. Higher abundances of less chlorinated congeners were seen in the less-industrialized areas compared to the industrialized areas. Differences in the transport abilities of different congeners, together with dechlorination of higher chlorinated congeners, is the most likely reasons for this. [ABSTRACT FROM AUTHOR]

The Yellow River Delta (YRD) is the second largest petrochemical base in China and the impact of human activities has been continuously increasing in recent decades, however, the contamination status of seldom monitored trace elements (SMTEs) in YRD has rarely been reported. This study evaluated the levels, vertical distributions, contamination status and sources of SMTEs in soil samples of three different land use types in YRD. The results indicated that the vertical distributions of SMTEs contents showed a gradually upward increasing trend for the soil profiles of black locust forest, while the SMTEs contents displayed a gradually upward decreasing trend for the soil profiles of cotton field. However, the SMTEs contents in the oil field area showed no significant difference among different depths. The vertical distributions of SMTEs were very likely related to the anthropogenic disturbance in the later stage. The environmental pollution status assessment of SMTEs showed obvious enrichment of Cs, Sn, and U in the soils of YRD. Moreover, the potential source analysis based on multivariate statistical methods indicated that Ga, Rb, Cs, Sc, Sn, Tl, Be, Bi, Ca and Mo were clustered together and positively correlated with Al, Fe, Mg and K, and may be mainly associated with geochemical weathering process, while the Ce, La, Th, U, Nb, Ta, and Hf may be impacted by both natural process and human activities. Though the SMTEs pollution status was not very serious, our results highlighted the non-negligible influence of anthropogenic activities on vertical distributions of SMTEs in three different land use types from YRD. Our results provide valuable information for understanding the vertical distribution and pollution status of SMTEs in YRD. • Non-negligible influence of anthropogenic activities on vertical distributions of SMTEs in YRD • SMTEs displayed an upward decreasing trend for the soil profiles of cotton field. • Obvious enrichment of Sn, Cs and U was observed in YRD soils. • Sources of most SMTEs are mainly related to the geochemical weathering process. [ABSTRACT FROM AUTHOR]

Mercury (Hg) has received increasing public attention owing to its high toxicity and global distribution capability via long-range atmospheric transportation. Guanzhong Basin (GB) is vital for the industrial and economic development of Shaanxi Province. To determine the concentration, spatial distribution, seasonal variation, sources, and health risks of particulate-bound mercury (PBM), PM 2.5 samples were collected at three sampling sites representing urban, rural, and remote areas during winter and summer in GB. The three sampling sites were in Xi'an (XN), Taibai (TB), and the Qinling Mountains (QL). The mean PBM concentrations in XN, TB, and QL in winter were 130 ± 115 pg m−3, 57.5 ± 47.3 pg m−3, and 53.6 ± 38.5 pg m−3, respectively, higher than in summer (13.7 ± 7.11 pg m−3, 8.01 ± 2.86 pg m−3, and 7.75 ± 2.85 pg m−3, respectively). PBM concentrations are affected by precipitation, meteorological conditions (temperature and mixed boundary layer), emission sources, and atmospheric transport. During the sampling period, the PBM dry deposition in XN, TB, and QL was 1.90 μg m−2 (2 months), 0.835 μg m−2 (2 months), and 0.787 μg m−2 (2 months), respectively, lower than the range reported in national megacities. According to backward trajectory and potential source contribution factor (PSCF) analysis, mercury pollution in XN is mainly affected by local pollution source emissions, whereas the polluted air mass in TB and QL originates from local anthropogenic emissions and long-distance atmospheric transmission. The non-carcinogenic health risk values of PBM in XN, TB, and QL in winter and summer were less than 1, indicating that the risk of atmospheric PBM to the health of the residents was negligible. [Display omitted] • Particulate-bound mercury (PBM) is higher in winter than in summer. • Higher PBM appeared at urban sites and lower values at rural and remote sites. • PBM in Guanzhong Basin is influenced by local and regional emissions. • The risk of atmospheric PBM to the health of residents is negligible. [ABSTRACT FROM AUTHOR]

The concentration changes of aerosols have attracted wide-ranging attention during the COVID-19 lockdown (CLD) period, but the studies involving aerosol optical properties (AOPs) are relatively insufficient, mainly AOD (fine-mode AOD (AODf) and coarse-mode AOD (AODc)), aerosol absorption optical depth (AAOD), and aerosol extinction coefficient (AEC). Here, the remote-sensing observations, Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) products, backward-trajectory, and potential-source-contribution models are used to assess the impact of AOPs, vertical distribution, and possible sources on the atmosphere environment in North China Plain (NCP), Central China (CC), Yangtze River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB) during the CLD period. The results demonstrate that both AOD (MODIS) and near-surface AEC (CALIPSO, 0.6) still occurred in some areas. Compared to previous years, there were increases in BC, OC (MERRA-2), and national raw coal consumption during CLD. Therefore, emissions from some key sectors (raw coal heating, thermal power generation, and residential coal) did not decrease, and this may have increased AODf during the CLD. Based on backward -rajectory and potential source contribution models, the study area was mainly influenced by local anthropogenic emissions, but some areas were also influenced by northwestern dust, Southeast Asian biomass burning, and marine aerosol transport. This paper underscores the importance of emissions from the residential sector and thermal power plants for atmospheric pollution in China and suggests that these sources must be taken into account in developing pollution-mitigation plans.

Large-scale open burning of straw residues causes seasonal and severe atmospheric pollution in Northeast China. Previous studies focused on the causes or assessment of atmospheric pollution in a single city. However, studies conducted on the interaction range, degree and policy control of pollutant transport on a large scale are still to be performed. In this study, we propose combined control of straw burning by dividing region the straw burning in Northeast China in recent 20 years, determining the transport routes between main cities, and analyzing the interaction characteristics of straw burning under different scenarios. The fire point data suggest that the most intense straw burning years in Northeast China in the past 20 years occurred in the range from 2014 to 2017, mainly after the autumn harvest (October–November) and before spring cultivation (March–April). The burning areas were concentrated in the belt of Shenyang-Changchun-Harbin, the border of the three provinces and Eastern-Inner Mongolia, and the surrounding area of Hegang and Jiamusi City. The lower number of fire points before 2013 indicates that high-intensity burning has not always been the case, while the sharp decline after 2018 is mainly due to scientific control of straw burning and increased comprehensive utilization of straw. Compared with S2, the PM2.5 concentrations increased by 6.2% in S3 and 18.7% in S4, indicating that burning in three or four provinces at the same time will significantly increase air pollution and exert a regional transmission effect. Straw burning in Northeast China is divided into six main regions based on correlation analysis and satellite fire monitoring. Under typical S3, the case analysis results indicate that there is regional transmission interaction between different cities and provinces, focusing on multi-province border cities, and it is affected by Northwest long airflow, and Southeast and Northeast short airflow. These results provide scientific and technological support for implementing the joint prevention and control plan for straw incineration in Northeast China.

Fine particulate matter (PM), including PM2.5 in pig houses, has received increasing attention due to the potential health risks associated with PM. At present, most studies have analyzed PM2.5 in Chinese pig houses utilizing natural ventilation. These results, however, are strongly affected by the internal structure and regional environment, thus limiting their applicability to non-mechanically ventilated pig houses. This experiment was carried out in an environmentally controlled pig house. The animal feeding operation and manure management in the house were typical for Southwest China. To reduce the influence of various environmental factors on PM2.5, the temperature and humidity in the house were maintained in a relatively stable state by using an environmental control system. The concentration of PM2.5 in the pig house was monitored, while the biological contents and chemical composition of PM2.5 were analyzed, and feed, manure, and dust particles were scanned using an electron microscope. Moreover, bacterial and fungal contents and some water-soluble ions in PM2.5 were identified. The results showed that the concentration of PM2.5 in the pig house was strongly affected by pig activity, and a phenomenon of forming secondary particles in the pig house was found, although the transformation intensity was low. The concentration of PM2.5 had negative correlations of 0.27 and 0.18 with ammonia and hydrogen sulfide, respectively. Interestingly, a stronger correlation was observed between ammonia and hydrogen sulfide and ammonia and carbon dioxide concentrations (the concentration of ammonia had stronger positive correlations with hydrogen sulfide and carbon dioxide concentrations at +0.44 and +0.59, respectively). The main potential sources of PM2.5 production were feed and manure. We speculate that manure could contribute to the broken, rough, and angular particles that formed the pig house PM2.5 that easily adhered to other components.

Ground-level ozone (O3) pollution has become a serious environmental issue in major urban agglomerations in China. To investigate the spatiotemporal patterns and regional transports of O3 in Beijing–Tianjin–Hebei (BTH-UA), the Yangtze River Delta (YRD-UA), the Triangle of Central China (TC-UA), Chengdu–Chongqing (CY-UA), and the Pearl River Delta urban agglomeration (PRD-UA), multiple transdisciplinary methods were employed to analyze the O3-concentration data that were collected from national air quality monitoring networks operated by the China National Environmental Monitoring Center (CNEMC). It was found that although ozone concentrations have decreased in recent years, ozone pollution is still a serious issue in China. O3 exhibited different spatiotemporal patterns in the five urban agglomerations. In terms of monthly variations, O3 had a unimodal structure in BTH-UA but a bimodal structure in the other urban agglomerations. The maximum O3 concentration was in autumn in PRD-UA, but in summer in the other urban agglomerations. In spatial distribution, the main distribution of O3 concentration was aligned in northeast–southwest direction for BTH-UA and CY-UA, but in northwest–southeast direction for YRD-UA, TC-UA, and PRD-UA. O3 concentrations exhibited positive spatial autocorrelations in BTH-UA, YRD-UA, and TC-UA, but negative spatial autocorrelations in CY-UA and PRD-UA. Variations in O3 concentration were more affected by weather fluctuations in coastal cities while the variations were more affected by seasonal changes in inland cities. O3 transport in the center cities of the five urban agglomerations was examined by backward trajectory and potential source analyses. Local areas mainly contributed to the O3 concentrations in the five cities, but regional transport also played a significant role. Our findings suggest joint efforts across cities and regions will be necessary to reduce O3 pollution in major urban agglomerations in China.

Purpose: Phthalate esters (PAEs) have been and remain the most widely used plasticizers worldwide, and they are also the most frequently detected environmental pollutants. It is known that the management style and agricultural inputs should play a critical role in the PAE contamination. However, the status of six priority controlled PAEs remains unclear in soils used for tobacco on farms that are under the compulsorily management of national tobacco company. Materials and methods: The samples included soils, water, and fertilizers were collected from tobacco cultivation sites in the Shandong province. The six priority controlled PAEs were extracted from the samples according to the reported methods, and they were analyzed using a GC-TQ-MS/MS under MRM mode. The hazard quotients and carcinogenic risks for people by gender and age were assessed first time by the recommended method of US Environmental Protection Agency. Results and discussion: Soils were contaminated by PAEs from 218.4 to 1168.9 μg kg−1, with the average value of 611.1 μg kg−1. More than 80% Σ6PAEs consisted of DBP and DEHP, and regional characteristics of Shandong province showed the highest content of DBP. Besides plastic film, agricultural inputs such as irrigation water and fertilizers were also the PAE sources. At present, the non-cancer risk has not exceeded the threshold of 1, and carcinogenic risk was still low in the range of 10−6–10−4 with the highest risk of DEHP exposure through dietary consumption. Conclusions: Pollution status of PAEs in tobacco cultivation soils and its health risk to Chinese people were already present at low levels. Thus, we should pay more attention to PAE contamination in order to prevent further deterioration, particularly for the DEHP exposure to middle-aged people. [ABSTRACT FROM AUTHOR]

Potential sources of inertia‐gravity waves (IGWs) in the lower stratosphere (z = 15–22 km) at Jang Bogo Station, Antarctica (74°37′S, 164°13′E) are investigated using 3‐year (December 2014 to November 2017) radiosonde data, including the 25‐month result (December 2014 to December 2016) analyzed in Yoo et al. (2018, https://doi.org/10.1029/2018JD029164, Part 1). For this investigation, three‐dimensional backward ray tracing calculations are conducted using the Gravity wave Regional Or Global RAy Tracer. Among 248 IGWs, 112, 68, and 68 waves are generated in the troposphere (z < 8 km), tropopause (z = 8–15 km), and lower stratosphere (z = 15–18.5 km), respectively. These waves mainly propagate from the northwestern and southwestern regions of Jang Bogo Station dominated by the prevailing westerlies between the upper troposphere and lower stratosphere. Potential sources of IGWs are categorized into orography, fronts, convection, and the flow imbalance including the upper‐tropospheric jet stream. In the troposphere, relatively large numbers of waves are associated with fronts (37) and orography (35) compared with convection (28). In the tropopause (stratosphere), 36 (42) waves, including 11 cases associated with the upper‐tropospheric jet stream, are excited by the flow imbalance. Waves related to the flow imbalance are characterized by low intrinsic frequency (1–2f), short vertical wavelength (1–2 km), and longer horizontal wavelength (50–1000 km), whereas the waves induced by the tropospheric sources have wider ranges of intrinsic frequency (1–20f) and vertical wavelengths (1–15 km) with relatively shorter horizontal wavelengths (less than 500 km). Key Points: Propagation and sources of inertia‐gravity waves (IGWs) are investigated using the Gravity wave Regional Or Global RAy Tracer (GROGRAT)Orography, fronts, convection, and the flow imbalance including the jet stream are suggested as potential sources for the observed IGWsRelationships between the observed IGWs and their sources are examined [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) have attracted attention due to the potential risk they pose to ecosystems and human health. A total of 169 groundwater samples were collected from four representative regions in order to analyze PFASs concentrations in China. The total concentration of PFASs (∑PFASs) in groundwater ranged from 0.05 to 198.80 ng L−1, with an average of 3.97 ng L−1. All targeted PFASs were detected in the studied areas. The detection frequency and average concentration of perfluorooctanoic acid (PFOA) were the highest (79.29% and 1.61 ng L−1, respectively). The contamination profiles of PFASs in each study area varied due to natural geographical conditions and human activities. According to the results of the potential source identification, the point sources of perfluorooctane sulfonate (PFOS) were mainly concentrated in Lanzhou, and the distribution of PFASs was slightly affected by atmospheric deposition in all the studied areas. The obtained concentrations of PFOA and PFOS may pose no threat to the residents due to water consumption. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) as substitutes for PBDEs have been widely detected in the marine environment, while little is known about the pollution characteristics and variation of OPEs in estuarine environments with complex hydrodynamic conditions and land-based input. Yangtze River Estuary (YRE) is a typical highly urbanized and industrialized estuary, with a complex hydrological environment and geochemical behavior. This study found that the concentrations of OPEs in both seawater and sediments in the YRE were higher in spring than in summer. Alkyl OPEs were the first contributor, with TnBP and TiBP as the main components, where the contribution of alkyl OPEs had exceeded 75 % in both seawater and sediments in spring, and 60 % in summer seawater, and even 80 % in sediments. In spring, OPEs peaked in the central to southern region near the YRE. In summer, OPEs were mainly concentrated in the southern branch waterway and southern nearshore area of the YRE and showed a decreasing trend to the northeast. The OPEs in the sediments were mainly concentrated in the Yangtze River Mud Area (YREMA) and the Zhe-Min Coastal Mud Area (ZMCMA). Based on the fugacity model and principal component analysis, sediments could be released into the aquatic environment as an endogenous source, and exogenous sources were mainly municipal and industrial sewage discharge sources, urban and marine traffic discharge sources, and atmospheric deposition sources. The ecological risk analysis showed that the Σ14OPEs had exhibited a low to moderate ecological risk in the southern branch waterway and the south-central region offshore. • The OPEs in seawater peaked in the southern branch waterway and southern nearshore area. • The OPEs in sediment were concentrated in the YREMA and the ZMCMA. • The OPEs concentration was higher in spring than in summer. • OPEs had low to moderate ecological risks in the water environment of the YRE. [ABSTRACT FROM AUTHOR]

There is accumulating evidence of the toxicity of organic ultraviolet absorbers (OUVAs); however, limited information is available regarding the presence of OUVAs in terrestrial environments and organisms. Therefore, this study was conducted to investigate the occurrence of 11 OUVAs in soils and typical plant species from an industrial metropolis in China. Total OUVA concentrations in soils ranged from 1.30 to 80.3 ng g−1 DW. Based on comparison with previously reported data, OUVA contamination in soil was not severe. Benzophenone and octocrylene were the dominant OUVAs in soils, with median contributions to total concentrations of 25% and 15%, respectively. Source assessment revealed that the observed OUVA contamination primarily originated from industrial activities and the use of personal care products. The concentration of 11 OUVAs in plants ranged from 159 to 4470 ng g−1 DW, at high levels. Our findings imply that great attention should be given to the presence of these chemicals in plants because of the risk they could pose as well as the potential for biomagnification as plants are eaten by insects and birds. Our results also indicate the necessity to further study the geochemical behavior of these chemicals in urban ecosystems in order to better manage the harmfulness to terrestrial ecological health caused by their exposure through the food chains. [Display omitted] • Eleven OUVAs were investigated in soils and plants from Tianjin, China. • Soil pollution was at a moderate level, but higher levels of OUVAs were found in plants. • Benzophenone and octocrylene were the dominant OUVAs in the soils and plants. • Industrial activities contributed importantly to the soil OUVAs. [ABSTRACT FROM AUTHOR]